Title: WASP-41b: A transiting hot Jupiter planet orbiting a magnetically-active G8V star Authors: P. F. L. Maxted (1), D. R. Anderson (1), A. Collier Cameron (2), C. Hellier (1), D. Queloz (3), B. Smalley (1), R. A. Street (4), A. H. M. J. Triaud (3), R. G. West (5), M. Gillon (6), T. A. Lister (4), F. Pepe (3), D. Pollacco (7), D. Segransan (3), A. M. S. Smith (1), S. Udry (3) ((1) Keele University, (2) University of St. Andrews, (3) Geneva University Observatory, (4) Las Cumbres Observatory, (5) Leicester University, (6) Liege University, (7) Queens University Belfast)
We report the discovery of a transiting planet with an orbital period of 3.05d orbiting the star TYC 7247-587-1. The star, WASP-41, is a moderately bright G8V star (V=11.6) with a metallicity close to solar ([Fe/H]=-0.08±0.09). The star shows evidence of moderate chromospheric activity, both from emission in the cores of the CaII H and K lines and photometric variability with a period of 18.3d and an amplitude of about 1%. The rotation period of the star implies a gyrochronological age for WASP-41 of 1.8Gyr with an error of about 15%. We have used a combined analysis of the available photometric and spectroscopic data to derive the mass and radius of the planet (0.93±0.06M_Jup, 1.21±0.06R_Jup). Further observations of WASP-41 can be used to explore the connections between the properties of hot Jupiter planets and the level of chromospheric activity in their host stars.